Savoury, earthy, mushroomy - none of them quite fit the bill when trying to describe the ever illusive umami taste. For the Japanese it is very much a part of the everyday vocabulary with the word itself  meaning ‘deliciousness', but in the West it is still a relatively new and slightly confusing subject.

So let's start at the beginning with kombu, yes, kombu the sea vegetable. One day the scientist Dr Ikeda Kikunae was sitting down to a dish of simmered tofu when it occurred to him that there was a taste there that could not be classified as any of the four known tastes: sweet, salty, bitter or sour; it was a fifth taste - umami. As the tofu itself had a relatively plain taste he felt that it must be the kombu which was responsible for this added dimension in the dish, so he set to work finding out what this taste was. And that is how he identified the amino acid glutamate, which kombu contains in abundance, as one of the main umami substances.

Just as sweetness, for example, can be derived from different substances such as glucose or fructose, umami too comes from a variety of substances. Since the discovery of kombu's glutamate content, other scientists have gone on to find other umami substances in fish, meat, mushrooms and other such products.

Although glutamate sounds similar to monosodium glutamate (MSG), it is important to point out that MSG is an unnatural, chemically synthesised product, while glutamate is a naturally occurring substance which is perfectly safe and healthy.

Unlike the other basic tastes, umami has the unique quality of bringing the other tastes together to create a more cohesive dish and a fuller taste in the mouth - just as the kombu brought out the best in the simmered tofu.

This, however, does not mean that umami is either a new concept or an exclusively Japanese taste. Umami-rich ingredients can be found in every part of the world and people have been playing with ways of enhancing their cooking with it for millenia. For example, in ancient Rome they had garum - a fermented fish sauce, similar to the modern South East Asian sauces, which was regularly used to season and enhance dishes. Equally, basic soups stocks all over the world tend to be rich in umami as is tomato ketchup and purée, essential store cupboard ingredients in most Western kitchens, and even Marmite.

If you want to try your own experiment, make two pans of risotto, one simply with rice, onions, thyme and stock, the other with the addition of dried porcini mushrooms, which have been rehydrated, and also the liquid that they soaked in. If you taste both risottos, you may find that the first is a little flat, as if something is missing. Now try the second and it will have a much more rounded taste and a greater depth of flavour too. This is due to the umami content of the dried porcini.

Umami is often associated with fish meat and dairy products, but vegan ingredients can also be rich in umami, here is a list:

Sea vegetables - while kombu has the highest concentration, all sea vegetable varieties contain umami
Shiitake - drying them also intensifies the umami content
Tomatoes - again, dried tomatoes have an even higher umami content
Soya beans - this includes soya bean products such as miso and soy sauce which are even higher in umami due to the fermentation process
Potatoes
Carrots
Onions
Garlic
Chinese cabbage
Asparagus
Green peas
Spinach
Nuts
Green tea
Sake

Here are some umami rich recipes:

Dashi
Nishime
Yudofu
Miso soup
Agedashi tofu
Hijiki with Shiitake, Carrot and Dried Tofu
Tofu, wakame and tomato salad
Hummus
Fusilli with Peanut Sauce
Minestrone

By Celia Plender